WASHINGTON, March 4 (UPI) -- U.S. President Barack Obama spoke about the situation in Ukraine -- and Russia's interpretation of international law -- on the sidelines of a speech about the FY2015 Budget on Tuesday.

Obama reiterated that "there is a strong belief that Russia's action" in occupying Ukraine's Crimean Peninsula "is violating international law."

In response to Russian President Vladimir Putin's assertion Tuesday at his own press conference in Russia that he maintains the right to deploy Russian troops into Ukraine, Obama joked, "I know President Putin seems to have a different set of lawyers making a different set of interpretations, but I don't think that's fooling anybody."

Obama went on to explain that if Putin has legitimate concerns for the safety of its citizens or Russian speakers in Ukraine, Russia should work within the international legal framework to address those concerns. Absent participation in the legal process, Putin seems to be attempting to manipulate Ukraine through the exertion of force. "That," Obama asserted, "is not how international law is supposed to operate."

"... although Russia has legitimate interests in what happens in a neighboring state, that does not give it the right to use force as a means of exerting influence inside of that state. ... if, in fact, there is any evidence out there that Russian speakers or Russian natives or Russian nationals are in any way being threatened, there are ways of dealing with that through international mechanisms.

"... the fact that we are still seeing soldiers out of their barracks in Crimea is an indication... what’s happening there is not based on actual concern for Russian nationals or Russian speakers inside of Ukraine, but is based on Russia seeking, through force, to exert influence on a neighboring country. That is not how international law is supposed to operate."

Obama said that while "Mr. Putin can throw a lot of words out there, ... the facts on the ground indicate that right now he’s not abiding by that principle." Russia can still, however, choose to engage "with the international community to help stabilize the situation." After all, Obama said, "we've sent a clear message that we are prepared to work with anybody if their genuine interest is making sure that Ukraine is able to govern itself."

Secretary of State John Kerry traveled to Kiev for meetings on Tuesday with Ukrainian leaders.

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